JP2017537214A - Compositions based on acrylic block copolymer blends - Google Patents

Abstract

(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer is (a) at least two A block polymer units, wherein each A block is at least 90 At least two A block polymer units having a glass transition temperature of 0 C and independently derived from a monoethylenically unsaturated monomer comprising a first (meth) acrylate monomer, and (b) at least one B block Polymer units comprising at least one B block polymer unit having a glass transition temperature of −30 ° C. or less and derived from a monoethylenically unsaturated monomer comprising a second (meth) acrylate monomer, A first polymer; (ii) polyvinyl acetal resin, polyvinyl acetate, and And a second polymer selected from at least one of the cellulose ester, the composition comprising a polymer blend, as described herein.

Description

  Acrylic block copolymer blends having desirable physical properties and free of halogen are disclosed.

  It would be desirable to identify compositions having physical properties (such as rheology) similar to some plasticized PVC (polyvinyl chloride) materials, such as those used in graphic marking films. There is also a need for materials that do not contain halogen groups, do not contain plasticizers, and / or do not contain acids. Advantageously, the compositions disclosed herein may provide properties over standard PVC materials, such as light transmission, weatherability, toughness, and the like.

In one aspect,
(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer is
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer A first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) A second polymer containing a polyvinyl acetal resin, which is obtained by acetalizing a polyvinyl alcohol resin with an aldehyde having 4 or more carbon atoms and an aldehyde having 3 or less carbon atoms, A polymer of
Polymer blends are described that are substantially free of plasticizers.

In another embodiment,
(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer is
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer A first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) a polymer blend is described comprising a second polymer selected from at least one of polyvinyl acetate and cellulose esters.

In another aspect, a method for producing a polymer blend comprising:
(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer is
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer Providing a first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) a second polymer comprising a polyvinyl acetal resin obtained by acetalizing a first polymer with an aldehyde having 4 or more carbon atoms and an aldehyde having 3 or less carbon atoms with the first polymer; Blending,
And the polymer blend is substantially free of plasticizer.

In yet another aspect, a method for producing a polymer blend comprising:
(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer is
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer Providing a first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) blending a first polymer with a second polymer selected from at least one of polyvinyl acetate and cellulose esters.

  The above summary is not intended to describe each embodiment. The details of one or more embodiments of the invention are also set forth in the description below. Other features, objects, and advantages will be apparent from the following description and the claims.

As used herein, the terms “a”, “an”, and “the” are used interchangeably and mean one or more.
“And / or” is used to indicate that one or both of the stated cases may occur, eg, A and / or B includes (A and B) and (A or B).
“(Meth) acrylate” means a polymeric material prepared from acrylates, methacrylates, or derivatives thereof.

  As used herein, the term “polymer” means a polymeric material that is a homopolymer or a copolymer. As used herein, the term “homopolymer” means a polymeric material that is the reaction product of one monomer. As used herein, the term “copolymer” means a polymeric material that is at least two different monomer reaction products.

  Further, in this specification, the description of ranges by endpoints includes all numbers included in the ranges (for example, 1 to 10 is 1.4, 1.9, 2.33, 5.75, Including 9.98).

  Also, in this specification, the phrase “at least one” means all numbers greater than 1 (eg, at least 2, at least 4, at least 6, at least 8, at least 10, at least 25, at least 50, at least 100, etc.).

  PVC (polyvinyl chloride) has been used in a wide variety of applications because of its low cost, biological and chemical resistance, and workability. However, the disadvantage of PVC is the chlorine content, which produces harmful byproducts and / or acidic byproducts when incinerated. Therefore, there is increasing interest in replacing PVC.

  A polymer comprising an acrylic block copolymer and (i) a polyvinyl acetal resin, (ii) polyvinyl acetate, (iii) a cellulose ester, and (iv) a second polymer selected from at least one of these combinations It has been discovered that the blend composition results in a composition similar in properties to plasticized PVC used in graphic marking film applications.

  First polymer

  The first polymer of the polymer blend includes at least one acrylic block copolymer. The polymer blend may comprise one acrylic block copolymer, two different acrylic block copolymers, or in some cases more than two different block copolymers.

  A “block copolymer” of the present disclosure is a copolymer in which chemically different blocks or sequences are covalently bonded to each other. The block copolymer comprises at least two different polymer blocks called A block and B block. The A block and the B block generally have different chemical compositions and different glass transition temperatures.

The block copolymers of the present disclosure include triblocks ((A-B-A) structure), multi-blocks (-(A-B) _n -structure), and star-shaped block copolymers ((A-B) _n -structure). It can be roughly divided into three types. Triblock structures and multiblock structures may be classified as linear block copolymers. Star block copolymers fall within the general class of block copolymer structures having a branched structure. Star block copolymers are also referred to as radial copolymers because they have a central point from which branches extend.

  The block copolymer of the present disclosure is an acrylic block copolymer comprising at least two A block polymer units and at least one B block polymer unit (ie, at least two A block polymer units are one B block polymer unit and Each covalently linked). Each A block is derived from a first (meth) acrylate monomer and the B block is derived from a second (meth) acrylate monomer.

  The A block tends to be more rigid than the B block (ie, the A block has a higher glass transition temperature than the B block). As used herein, the term “glass transition temperature” or “Tg” refers to a polymeric material from a glassy state (eg, brittleness, hardness and stiffness) to a rubbery state (eg, flexible and elastomeric). It means the temperature to transition. Tg can be measured using techniques such as, for example, Differential Scanning Calorimetr (DSC) or Dynamic Mechanical Analysis (DMA).

  The block copolymer typically has a regular multiphase morphology at temperatures ranging from at least about 25 ° C to about 150 ° C. Since the A block has a solubility parameter that is sufficiently different from the B block, the A block phase and the B block phase are usually separated. Block copolymers can have different regions of reinforced A block domains (eg, nanodomains) within a softer and more elastomeric B block matrix. That is, block copolymers often have separate, discontinuous A block phases within a substantially continuous B block phase.

式（Ｉ）において、Ｒ^１は、アルキル、アリール、又はアラルキル（即ち、アリール基で置換されたアルキル）である。好適なアルキル基は、多くの場合、１〜６個の炭素原子、１〜４個の炭素原子、又は１〜３個の炭素原子を有する。アルキル基が２個より多い炭素原子を有する場合、アルキル基は分枝状又は環状の可能性がある。好適なアリール基は、多くの場合、６〜１２個の炭素原子を有する。好適なアラルキル基は、多くの場合、７〜１８個の炭素原子を有する。 In the A block polymer unit, the (meth) acrylate monomer reacts to form an A block. A blocks tend to provide structural strength and cohesive strength to (meth) acrylate block copolymers. Any (meth) acrylate monomer can be used as long as the resulting A block Tg is at least 90 ° C. The (meth) acrylate monomer can be, for example, an alkyl methacrylate, aryl methacrylate, or aralkyl methacrylate of the formula (I).

In formula (I), R ¹ is alkyl, aryl, or aralkyl (ie, alkyl substituted with an aryl group). Suitable alkyl groups often have 1 to 6 carbon atoms, 1 to 4 carbon atoms, or 1 to 3 carbon atoms. If the alkyl group has more than 2 carbon atoms, the alkyl group may be branched or cyclic. Suitable aryl groups often have 6 to 12 carbon atoms. Suitable aralkyl groups often have 7 to 18 carbon atoms.

  Representative alkyl methacrylates according to formula (I) include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, or combinations thereof. In addition to the monomer of formula (I), isobornyl methacrylate can also be used. Representative aryl methacrylates according to formula (I) include phenyl methacrylate. Exemplary aralkyl methacrylates according to formula (I) include benzyl methacrylate, 2-phenoxyethyl methacrylate, or combinations thereof.

  The A blocks of the block copolymer may be the same or different. In some block copolymers, each A block is poly (methyl methacrylate). In a more specific example, the block copolymer can be a triblock or star block copolymer where each block is poly (methyl methacrylate).

  The weight average molecular weight (Mw) of each A block is usually at least about 5,000 g / mol. In some block copolymers, the weight average molecular weight of the A block is at least about 8,000 g / mol or at least about 10,000 g / mol. The weight average molecular weight of the A block is usually less than about 30,000 g / mole or less than about 20,000 g / mole. The weight average molecular weight of the A block is, for example, from about 5,000 to about 30,000 g / mol, from about 10,000 to about 30,000 g / mol, from about 5,000 to about 20,000 g / mol, or about 10,000. Up to about 20,000 g / mol.

  Each A block has a Tg of at least 90 ° C. In some embodiments, the A block has a Tg of at least 95 ° C, at least 100 ° C, or at least 120 ° C. In many cases, Tg is 200 ° C. or lower, 190 ° C. or lower, or 180 ° C. or lower. For example, the Tg of the A block can be 100 ° C to 200 ° C, 100 ° C to 180 ° C, or 120 ° C to 180 ° C.

式（ＩＩ）において、Ｒ^２は、炭素１〜２２個を有するアルキル、又は炭素２〜２０個と酸素又は硫黄から選択されるヘテロ原子１〜６個とを有するヘテロアルキルである。アルキル基又はヘテロアルキル基は、線状、分枝状、環状又はこれらの組み合わせとすることができる。 B block polymer units are derived from (meth) acrylate monomers. The B block can be derived from an acrylate monomer of formula (II).

In the formula (II), R ² is alkyl having 1 to 22 carbons, or heteroalkyl having 2 to 20 carbons and 1 to 6 heteroatoms selected from oxygen or sulfur. The alkyl group or heteroalkyl group can be linear, branched, cyclic, or combinations thereof.

  In some embodiments, the monomer according to Formula II is an alkyl (meth) acrylate having an alkyl group with 4-18, 4-10, 4-6, or 4 carbon atoms. In some examples, the monomer is an acrylate. Polymers made from acrylate monomers tend to be less rigid than their methacrylate counterparts.

  Representative alkyl acrylates of formula (II) that can be used to form B block polymer units include ethyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, n-pentyl acrylate, isoamyl. Acrylate, n-hexyl acrylate, 2-methylbutyl acrylate, 2-ethylhexyl acrylate, 4-methyl-2-pentyl acrylate, n-octyl acrylate, 2-octyl acrylate, isooctyl acrylate, isononyl acrylate, decyl acrylate, isodecyl Examples include acrylate, lauryl acrylate, isotridecyl acrylate, octadecyl acrylate, dodecyl acrylate, or combinations thereof.

  Exemplary heteroalkyl acrylates of formula (II) that can be used to form B block polymer units include 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, or combinations thereof.

  For example, some alkyl methacrylates, such as alkyl methacrylates having alkyl groups with more than 6-20 carbon atoms, can be used to prepare the B block. Exemplary alkyl methacrylates include 2-ethylhexyl methacrylate, isooctyl methacrylate, n-octyl methacrylate, isodecyl methacrylate, lauryl methacrylate, or combinations thereof. Similarly, some heteroalkyl methacrylates, such as 2-ethoxyethyl methacrylate, can be used.

  The B block typically has a Tg of −30 ° C. or less. In some embodiments, the B block has a Tg of −40 ° C. or lower, −50 ° C. or lower, or −60 ° C. or lower. In many cases, Tg is -80 ° C or higher, -70 ° C or higher, or -50 ° C or higher. For example, the Tg of the B block can be -70 ° C to -30 ° C, -60 ° C to -30 ° C, or -50 ° C to -30 ° C.

  The weight average molecular weight of the B block is usually at least about 30,000 g / mol. In some block copolymers, the weight average molecular weight of the B block is at least about 40,000 g / mol, or at least about 50,000 g / mol. The weight average molecular weight is approximately 200,000 g / mol or less. The weight average molecular weight of the B block is usually 150,000 g / mol or less, about 100,000 g / mol or less, or about 80,000 g / mol or less. In some block copolymers, the weight average molecular weight of the B block is from about 30,000 g / mol to about 200,000 g / mol, from about 30,000 g / mol to about 100,000 g / mol, from about 30,000 g / mol. About 80,000 g / mol, about 40,000 g / mol to about 200,000 g / mol, about 40,000 g / mol to about 100,000 g / mol, or about 40,000 g / mol to about 80,000 g / mol It is.

  This block copolymer usually contains 20 to 70% by weight A block and 30 to 80% by weight B block, based on the weight of the block copolymer. For example, the copolymer may comprise 20 to 70 weight percent A block and 30 to 80 weight percent B block, 25 to 65 weight percent A block and 35 to 75 weight percent B block, 30 to 60 weight percent A block, and Contains 40-70 weight percent B block, 35-60 weight percent A block and 40-65 weight percent B block, or 35-55 weight percent A block and 45-65 weight percent B block it can. Larger amounts of A block tend to increase the stiffness or modulus of the copolymer, which can be used to optimize composition properties such as mechanical strength and modulus.

  In one particular embodiment, the acrylic block copolymer is a triblock copolymer, each A block comprising a reaction product of an alkyl methacrylate monomer, and the B block comprising a reaction product of an alkyl (meth) acrylate monomer. For further discussion regarding the selection of these A and B block copolymers and monomers, see, for example, US Patent Application No. 61/057532 (Joseph et al.).

  The block copolymer may include other functional monomer units, but they are typically randomly distributed throughout one or more acrylic blocks in the block copolymer. Blocks A and / or B can include other (meth) acrylic comonomers having various functional groups known to those skilled in the art, such as acid, amide, amine, hydroxyl, epoxy, or alkoxy functional groups. For example, polar monomers can be used to adjust Tg (as long as Tg is maintained within the claimed Tg) or block cohesion. Furthermore, polar monomers can function as reactive sites for chemical or ionic crosslinking, if desired. Typical polar monomers include (meth) acrylic acid, (meth) acrylamides such as N-alkyl (meth) acrylamide and N, N-dialkyl (meth) acrylamide, hydroxyalkyl (meth) acrylate, and N-vinylpyrrolidone. And N-vinyl lactams such as, but not limited to, N-vinyl caprolactam. In one embodiment, the A block can contain 10, 8, 6, or optionally up to 4 weight percent of the polar monomer, while the B block contains about 30, 25, 20, 15 polar monomer. Or in some cases up to 10 weight percent.

  Any technique that results in a well-controlled block and block copolymer structure can be used to prepare the block copolymer. As used herein, the term “well controlled” has at least one of the properties of controlled molecular weight, low polydispersity, well-defined blocks, or high purity blocks. A block or block copolymer structure is meant.

  Blocks and block copolymers are usually low in polydispersity. As used herein, the term “polydispersity” is a measure of molecular weight distribution and refers to the weight average molecular weight (Mw) divided by the number average molecular weight (Mn) of the polymer. Materials all having the same molecular weight have a polydispersity of 1.0, and materials having a molecular weight greater than one have a polydispersity of greater than 1.0. Polydispersity can be measured, for example, using gel permeation chromatography. Some blocks and block copolymers have a polydispersity of 2.0 or less, 1.5 or less, or 1.2 or less.

  In some block copolymers, the boundary between the nanodomain containing the A block and the continuous phase containing the B block is well defined (ie, the boundary is used for both tapered structures-A and B blocks). Essentially free of structures derived from the monomer to be produced).

  Some A blocks and B blocks are of high purity. For example, the A block can be essentially free of segments derived from the monomers used during the preparation of the B block. Similarly, the B block can be essentially free of segments derived from the monomers used during the preparation of the A block.

  A method for producing an acrylic block copolymer is known in the art as described, for example, in US Pat. No. 6,806,320 (Everaerts et al.). KULARITY ", and also from Arkema Chemicals Co. , Columbes, France.

  The acrylic block copolymers of the present disclosure have a number average molecular weight (Mn) of at least 46,000 daltons, at least 100,000 daltons, at least 300,000 daltons, at least 1,000,000 daltons, or in some cases at least 1,600 1,000 daltons may be used. In one embodiment, the acrylic block copolymer has a molecular weight of 75,000-150,000 daltons.

  In one embodiment, the acrylic block copolymer comprises PMMA (polymethylmethacrylate) at least 25, 30, or in some cases 35% by weight and up to 70, 65, 60, or in some cases 55% by weight.

  In some embodiments, more than one block copolymer is used. For example, two or more block copolymers having different weight average molecular weights, or two or more block copolymers having different concentrations of block polymer units can be used. The use of multiple block copolymers with different weight average molecular weights or block polymer unit amounts can, for example, improve the mechanical properties of the composition.

  Second polymer

  The acrylic block copolymer is blended with a second polymer selected from at least one of (i) polyvinyl acetal resin, (ii) polyvinyl acetate, and (iii) cellulose ester.

  The second polymer is selected to form a polymer blend that is compatible with the first polymer. In other words, it is an immiscible polymer blend that exhibits macroscopically uniform physical properties (usually caused by sufficiently strong interactions between component polymers) under the intended application conditions. In the present disclosure, the second polymer listed is selected based on Tg and molecular weight.

In one embodiment, the second polymer is a polyvinyl acetal resin. The polyvinyl acetal resin is produced by acetalizing a polyvinyl alcohol resin with an aldehyde having 4 or more carbon atoms and an aldehyde having 3 or less carbon atoms. The polyvinyl acetal resin generally has a repeating unit represented by Formula 1.

In Formula I, R ³ represents an alkyl residue or hydrogen atom of an aldehyde having 3 or less carbon atoms used in the acetalization reaction, and R ⁴ represents 4 or more carbons used in the acetalization reaction. Represents an alkyl residue of an aldehyde having an atom (wherein the number of carbon atoms of the alkyl residues R ³ and R ⁴ is an integer i obtained by subtracting 1 from the number of carbon atoms of the aldehyde used in the acetalization reaction) And when i is zero, R ³ represents a hydrogen atom), k ₃ represents the molar ratio of vinyl alcohol units acetalized with an aldehyde having 3 or less carbon atoms, and k ₄ is Represents the molar ratio of vinyl alcohol units acetalized with an aldehyde having 4 or more carbon atoms, l is the molar ratio of vinyl alcohol units not acetalized M represents the molar ratio of vinyl acetate units. Note that m may be zero. The arrangement of units is not particularly limited to the arrangement order shown in Formula 1. Polyvinyl acetal resins are typically random copolymers, but block copolymers and tapered block copolymers can provide similar benefits as random copolymers.

  With respect to the polyvinyl alcohol resin, the polyvinyl alcohol resin is not particularly limited, and may be generated by any method. For example, it may be generated by saponifying polyvinyl acetate or the like with alkali, acid, or aqueous ammonia. . Furthermore, a copolymer of vinyl alcohol and a monomer copolymerizable with vinyl alcohol, such as an ethylene-vinyl alcohol copolymer resin or a partially saponified ethylene-vinyl alcohol copolymer resin, can be used as the polyvinyl alcohol resin. Furthermore, for example, a modified polyvinyl alcohol resin into which a carboxylic acid is partially introduced can be used. These polyvinyl alcohol resins can be used alone or in combination of two or more.

  Examples of aldehydes having 3 or less carbon atoms used for the production of polyvinyl acetal resin include formaldehyde (including paraformaldehyde), acetaldehyde (including paraacetaldehyde), propionaldehyde and the like. Examples of aldehydes having 4 or more carbon atoms used for the production of polyvinyl acetal resins include butyraldehyde, isobutyraldehyde, n-octyl aldehyde, amyl aldehyde, hexyl aldehyde, heptyl aldehyde, 2-ethylhexyl aldehyde, cyclohexyl Examples include aldehyde, furfural, glyoxal, glutaraldehyde, benzaldehyde, 2-methylbenzaldehyde, 3-methylbenzaldehyde, 4-methylbenzaldehyde, p-hydroxybenzaldehyde, m-hydroxybenzaldehyde, phenylacetaldehyde, β-phenylpropionaldehyde and the like. Methods for producing polyvinyl acetal resins are known in the art, see for example US Patent Application Publication No. 2011/0112247 (Tokuchi et al.). This is incorporated herein by reference.

  The content of polyvinyl alcohol in the polyvinyl acetal resin is typically in the range of about 10 to 30% by weight. In some embodiments, the polyvinyl alcohol content ranges from about 15-25% by weight. Accordingly, “l” is selected accordingly.

  The content of polyvinyl acetate in the polyvinyl acetal resin can be zero or in the range of 1 to 8% by weight. In some embodiments, the polyvinyl acetate content ranges from about 1-5% by weight. Accordingly, “m” is selected accordingly.

The content of polyvinyl acetal (eg, butyral) in the polyvinyl acetal resin typically ranges from 65% to 90% by weight. In some embodiments, the content of polyvinyl acetyl (eg, butyral) ranges from about 70 or 75 to 80 or 85% by weight. Therefore, “k _3/2 , k _4/2 ” is selected accordingly.

  One of the most common polyvinyl acetal resins is polyvinyl butyral, although other polyvinyl acetal resins are also contemplated in this disclosure. Polyvinyl butyral is commercially available from Kuraray under the trade name “MOWITAL” and from Solutia under the trade name “BUTVAR”.

  The polyvinyl acetal resin typically has an average molecular weight (Mw) of at least 10,000 g / mol, 15,000 g / mol, 20,000 g / mol, or in some cases 25,000 g / mol and 150,000 g /, 100,000 g / mol, 75,000 g / mol, or in some cases, 70,000 g / mol or less.

  In some embodiments, the polyvinyl acetal resin has a Tg of 60-75 ° C, or in some cases 80 ° C. In some embodiments, the Tg of the polyvinyl acetal (eg, butyral) resin is at least 65-70 ° C. If other aldehydes are used in the preparation of the polyvinyl acetal resin, the Tg may vary. For example, when n-octyl aldehyde is used, Tg may be 65 ° C. or less than 60 ° C.

In one embodiment, the second polymer is polyvinyl acetate. Polyvinyl acetate (containing repeating units of —CH ₂ —CH (OC (═O) CH ₃ ) —) can be prepared by polymerization of vinyl acetate monomer. Typically these are homopolymers, but small amounts (10, 5, 2, 1, or in some cases less than 0.5 mol%) of other polymerized monomers may be present.

  Polyvinyl acetate typically has an average molecular weight (Mw) of at least 80,000 g / mol, 100,000 g / mol, or in some cases 110,000 g / mol, 700,000 g /, 500,000 g / mol. Mole or in some cases up to 400,000 g / mol. In some embodiments, the polyvinyl acetate has a Tg of 30-45 ° C.

  In one embodiment, the second polymer is a cellulose ester, preferably an aliphatic ester (ie, an ester having an aliphatic acyl group). Examples of the aliphatic acyl group include an acetyl group, a propynyl group, and a butynyl group. Representative cellulose esters include cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate benzoate, cellulose propionate, and cellulose butyrate. The content of acetyl, propionyl and butyryl can be measured together with the hydroxy content by the method defined in ASTM-D817-96. In one embodiment, the cellulose ester has a hydroxy group content of 0.8 to 5% by weight of the total second polymer.

  Depending on the cellulose ester selected, the molecular weight and Tg ranges may vary. In some embodiments, the cellulose ester typically has an average molecular weight (Mw) of at least 15,000 g / mol, 25,000 g / mol, 50,000 g / mol, or in some cases 75,000 g / mol. 300,000 g / 240,000 g / mol or, in some cases, 200,000 g / mol or less. In some embodiments, the cellulose acetate butyrate has a Tg of 85 ° C to 140 ° C, or in some cases 100 ° C to 140 ° C. For example, in some embodiments, the cellulose acetate propionate has a Tg of 120 ° C to 160 ° C, or in some cases 140 ° C to 160 ° C.

  In the present disclosure, a first polymer is blended with a second polymer using techniques known in the art to form a polymer blend. For example, the polymer can be mixed using a mixing / kneading device such as a Banbury mixer, an extruder, or a mixing roll to form a uniform composition. Alternatively, the polymer may be dissolved or suspended in a solution and then cast into a film. If used, the additive can be added simultaneously with the first and second polymers, or the additive can be premixed with one of the polymers and then added to the other polymer.

  In one embodiment, the composition of the present disclosure may be formed into a film by coating or extrusion, or formed into a part.

  In one embodiment, based on the total weight of the first polymer and the second polymer, at least 30, 40, or even 50%, and not more than 60, 70, or 80% by weight of the first polymer (at least One acrylic block copolymer) is used. In one embodiment, at least 20, 30, or even 40% of the total weight of the first polymer and the second polymer, and no more than 50, 60, or 70% by weight of the second polymer is used. Is done.

  In one embodiment, the first polymer comprises at least two different acrylic block copolymers.

  In one embodiment, the composition consists essentially of a first polymer and a second polymer. This means that the first and second polymers comprise at least 90, 92, 95, or in some cases 98% by weight of the total composition.

In one embodiment, a composition comprising a blend of a first polymer and a second polymer includes an additive such as a flame retardant, a bioactive filler, or other fillers known in the art (TiO ₂ ). In addition. In one embodiment, the composition comprises 30, 20, 10, 5, or optionally less than 1 part filler per 100 parts (pph) of the first polymer and the second polymer.

  In one embodiment, the composition comprising the acrylic block copolymer and the second polymer blend further comprises a plasticizer. A plasticizer is a material used to modify the processability or finish properties (eg, flexibility or durability) of a polymer composition and is typically a liquid. The plasticizer is selected based on compatibility with the polymer and molecular weight. Representative plasticizers are known in the art and include, for example, phthalic acid esters, sebacic acid esters (eg, sebacic acid polyesters), adipic acid esters (eg, adipic acid polyesters), phthalic acid esters (eg, terephthalic acid) Ester), dibenzoic acid ester, glutaric acid ester (for example, glutaric acid polyester), azelaic acid ester, and combinations thereof. Commercially available polymer plasticizers include HallStar Co. , Chicago, IL under the trade names “HALLSTAR”, “PARAPLEX”, and “PLASTHALL”.

In some embodiments, the polymer blend composition (and the article comprising the polymer blend) is substantially free of plasticizer (in other words, 1, 0.5, or optionally based on the amount of polymer blend). Less than 0.1% by weight of plasticizer is used, or no plasticizer is detected in the composition). In other embodiments, plasticizers may be used. If a plasticizer is used, it may be used at a level of 1 to 20 phh, 1 to 10 phh, or even 1 to 3 phh (parts of plasticizer per 100 parts) of the first and second polymers. Whether a plasticizer is used may be determined by the choice of the first and second polymers and / or additional components added. For example, if the cellulose ester is the second polymer, for a given viscosity, the higher the butyryl content of the cellulose ester, the higher the flexibility and the lower the need for a plasticizer to achieve the given flexibility. . In some embodiments, a filler such as a brightener (eg, TiO ₂ ) may be added to the polymer blend. The more filler added to the composition, the harder the composition, so a plasticizer may be used to soften the polymer blend composition.

  In one embodiment, the polymer blend composition (and an article comprising the polymer blend) further comprises conventional tackifiers, which are known in the art (eg, rosin and its derivatives, polyterpenes and aromatic modified polyterpene resins). , Coumarone-indene resins, hydrocarbon resins such as alpha pinene resins, beta pinene resins, limonene resins, aliphatic hydrocarbon resins, aromatic modified hydrocarbon resins, and the like. A tackifier may be used to further modify the softening temperature of the polymer blend composition for a particular application only if the polymer blend composition is non-tacky. In one embodiment, the polymer blend composition (and the article comprising the polymer blend) comprises a first polymer and a second polymer of 50, 40, 30, 20, 10, 5, 2, 1, 0.5 pph. Less than (number of copies per 100 parts).

  In one embodiment, a solvent may be added to the blend of the first polymer and the second polymer to enable coating and / or to produce a propellant. In one embodiment, the composition is at least 60, 65, or in some cases 70% and up to 75, or in some cases, based on the total weight of the first polymer, second polymer and solvent. Contains 80% by weight of solvent. Exemplary solvents include alcohols (eg, isopropanol and ethanol), acetone, toluene, methyl ethyl ketone, alkyl acetates (eg, ethyl acetate, and tert-butyl cyclohexane acetate), and mixtures thereof. Preferably, in one embodiment, the solvent is a non-VOC (volatile organic compound) solvent according to 40 CFR (Code of Federal Regulations) § 51.100 at the filing date. Exemplary non-VOC solvents include tert-butyl acetate, dimethyl carbonate, methyl acetate, acetone, and mixtures thereof.

In one embodiment, the polymer blend of the present disclosure comprising a first polymer and a second polymer has properties similar to PVC. For example, in one embodiment, the polymer blend has a first modulus of elasticity of at least 10 ⁶ Pa, 5 × 10 ⁶ Pa, or in some cases 10 ⁷ Pa at 35 ° C. and a first elasticity at 150 ° C. The second modulus of elasticity is at least an order of magnitude less than the modulus and the tan delta at 150 ° C. is 1.1, 1.0, or in some cases less than 0.9.

  Because block copolymers have a saturated polymer backbone, in one embodiment, articles made from these polymeric materials tend to be resistant to climate-induced (eg, UV-induced and oxidation-induced) degradation. is there.

  In one embodiment, the resulting article can be optically transparent. As used herein, the term “optically transparent” has a luminous transmittance of at least about 90 percent, a haze of less than about 2 percent, and an opacity of less than about 1 percent in the wavelength range of 400-700 nm. Means material. Both luminous transmittance and haze can be measured using, for example, ASTM-D1003-95. Optically transparent materials tend to be visually free of bubbles.

  The polymer blend can be made into a film by coating or casting, or molded into an article. In one embodiment, the polymer blend is a graphic film, a printable film, or a graphic protective film.

  Graphic film is applied to vehicles such as buildings, pavements, windows, or passenger cars, cans, buses, trucks, trams, for example for the purpose of advertising and decoration, for example, images, graphics, characters and / or information Used to. Many surfaces, eg, vehicles, are irregular and / or not flat. As a graphic film, a film that can be applied to a curved portion, a dent, or a projection on the surface of a substrate so that the film can be stretched around the curved portion or the projection, or can be pushed into a dent without breaking or delaminating the film. It is desirable to have This property is commonly referred to as flexibility. It is also desirable that the film / adhesive composite does not delaminate ("lift") from the substrate surface after application. The graphic film may be any color. The graphic film may be imageable (i.e., accept printing and / or graphics) and may exhibit good weather resistance for outdoor applications.

The resulting articles and polymer blend compositions disclosed herein are not adhesives. The resulting article is preferably non-tacky to the touch at room temperature (25 ° C.), preferably (120 ° F.) up to 50 ° C. (eg, storage or delivery). The composition is non-tacky, meaning that it does not meet the Dahlquist criteria for sticking. In other words, the blend composition of the present disclosure has a storage modulus (G ′) of greater than 3 × 10 ⁵ Pascals at 25 ° C. for a test frequency of 1 radians / second. Thus, the resulting article and / or polymer blend composition is not a pressure sensitive adhesive according to the Dahlquist standard.

  Exemplary embodiments include the following.

Embodiment 1
(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer is
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer A first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) A second polymer containing a polyvinyl acetal resin, which is obtained by acetalizing a polyvinyl alcohol resin with an aldehyde having 4 or more carbon atoms and an aldehyde having 3 or less carbon atoms, A polymer of
And a polymer blend substantially free of plasticizer.

  Embodiment 2 The polymer blend of embodiment 1, wherein the polyvinyl acetal resin comprises polyvinyl butyral.

Embodiment 3
(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer is
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer A first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) a polymer blend comprising a second polymer selected from at least one of polyvinyl acetate and cellulose ester.

  Embodiment 4 The polymer blend of embodiment 3, wherein the cellulose ester is selected from cellulose acetate propionate and cellulose acetate butyrate.

  Embodiment 5 The polymer blend of any one of the preceding embodiments, wherein the first polymer comprises 20-60% by weight of at least two A block polymer units.

  Embodiment 6 The polymer blend of any one of the preceding embodiments, wherein the first polymer comprises a first acrylic block copolymer and a second acrylic block copolymer.

  Embodiment 7 The first acrylic block copolymer comprises 45-60% by weight of at least two A block polymer units, and the second acrylic block copolymer comprises 20-45% by weight of at least two A block polymer units. 7. The polymer blend of embodiment 6.

  Embodiment 8 The polymer blend of any one of the preceding embodiments, wherein the first (meth) acrylate monomer is selected from at least one of methyl methacrylate, isobornyl acrylate, and methyl acrylate.

  Embodiment 9 Any one of the preceding embodiments, wherein the second (meth) acrylate monomer is selected from at least one of butyl acrylate, isooctyl acrylate, n-octyl acrylate, and 2-ethylhexyl acrylate. The polymer blend described in 1.

  Embodiment 10 The polymer blend of any one of the preceding embodiments, comprising 30 to 80 wt% acrylic block copolymer based on the total weight of the first polymer and the second polymer.

  Embodiment 11 The polymer blend of any one of the preceding embodiments, comprising 20 to 70% by weight of the second polymer relative to the total weight of the first polymer and the second polymer.

  Embodiment 12 The polymer blend of any one of the preceding embodiments, further comprising a tackifier.

  Embodiment 13 The polymer blend of embodiment 12, wherein the amount of tackifier is less than 30 pph of the first polymer.

  Embodiment 14 The polymer blend of any one of the preceding embodiments, wherein the polymer blend is substantially non-tacky.

  Embodiment 15 The polymer blend of any one of the previous embodiments comprising an additive.

  Embodiment 16 The polymer blend of embodiment 15, wherein the additive is a flame retardant.

  Embodiment 17 The polymer blend of any one of the preceding embodiments, further comprising a solvent.

  Embodiment 18 The polymer blend of embodiment 17, comprising 60-80 wt% solvent, based on the total weight of the first polymer, second polymer and solvent.

  Embodiment 19 The polymer blend of any one of the preceding embodiments, consisting essentially of a first polymer and a second polymer.

Embodiment 20 A first elastic modulus that is at least 10 ⁶ Pa at 35 ° C., a second elastic modulus that is at least an order of magnitude less than the first elastic modulus at 150 ° C., and a tan delta of 1 at 150 ° C. The polymer blend of any one of the preceding embodiments, wherein the polymer blend is less than 1.

  Embodiment 21 The polymer blend of any one of Embodiments 3 to 20, further comprising a plasticizer.

  Embodiment 22 The polymer blend of embodiment 21, comprising less than 20 pph plasticizer based on the total weight of the first polymer and the second polymer.

  Embodiment 23 An article comprising a polymer blend according to any one of the preceding embodiments.

Embodiment 24. A method for producing a polymer blend, comprising:
(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer is
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer Providing a first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) blending an acrylic block copolymer with a second polymer comprising a polyvinyl acetal resin obtained by acetalizing a polyvinyl alcohol resin with an aldehyde having 4 or more carbon atoms and an aldehyde having 3 or less carbon atoms To do
And the polymer blend is substantially free of plasticizer.

  Embodiment 25 The method of embodiment 24, wherein the polyvinyl acetal resin comprises polyvinyl butyral.

Embodiment 26. A method for producing a polymer blend, comprising:
(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer is
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer Providing a first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) blending the acrylic block copolymer with a second polymer selected from at least one of polyvinyl acetate and cellulose ester.

  Embodiment 27 The method of embodiment 26, wherein the cellulose ester is selected from cellulose acetate propionate and cellulose acetate butyrate.

  The advantages and embodiments of the present disclosure are further illustrated by the following examples, but the specific materials and amounts listed in these examples, as well as other conditions and details, should be construed to unduly limit the present invention. Should not be done. In these examples, all percentages, percentages, and ratios are by weight unless otherwise indicated.

  Unless otherwise stated or apparent, all materials are commercially available from, for example, Sigma-Aldrich Chemical Company Milwaukee, WI, or are known to those skilled in the art.

In the examples below, the following abbreviations are used. g = gram, kg = kilogram, min = minute, hr = hour, mol = mol, cm = centimeter, mm = millimeter, Pa = pascal, psi = pressure per square inch, phr = parts per hundred parts of rubber, rpm = number of revolutions per minute, MPa = megapascals, and wt = weight.

  Formulation and hot melt mixing:

  Each sample (25 g) listed in the table (excluding freshly used CEO) was dry blended with 0.2 phr antioxidant and then filled into a Brabender 25 gram bowl mixer. These ingredients were mixed at 165 ° C. for 5 minutes at 50 rpm. The samples were then hot pressed using a Carver platen press with a platen maintained at 165 ° C. for 1 minute between sheets of release polyester film to a thickness in the range of 100-175 micrometers. The film was then conditioned overnight in a constant temperature and humidity room maintained at 72 ° F. and 50% relative humidity before testing.

  Dynamic mechanical analysis:

Samples were tested for dynamic mechanical properties in an 8 mm diameter parallel plate rotational shear geometry using a rheometer (AR2000EX dynamic mechanical analyzer, TA Instrument Inc. New Castle, DE). The films were stacked to obtain a test sample thickness of 1-2 mm. Using a constant angular vibration frequency of 1 radians / second, with a strain of 1%, the sample temperature was increased from 120 ° C. to −20 ° C. at a rate of 3 ° C./min until the shear stress exceeded 1 × 10 ⁵ Pa. Lowered. The device then maintained 1 × 10 ⁵ Pa and transitioned to a constant stress mode where the strain decreased with increasing sample modulus. The temperature was then raised from 120 ° C. to 200 ° C. with a constant strain of 5%. Storage modulus (G ′) and tan delta (tan δ) were recorded. Selected values for these parameters at 35 ° C and 150 ° C were tabulated.

  Tensile strength and elongation at break: Instron Corp. The samples were tested using an Instron 4501 tensile tester sold by Norwood, MA. A 1 inch long (25.4 mm) x 0.5 inch wide (12.7 mm) sample is held on the upper and lower jaws of the Instron and pulled to break at a rate of 12 inches per minute (304.8 mm / min) It was. The tensile strength in psi (and MPa) and elongation at break in percent (%) were recorded. The test was performed at controlled laboratory conditions at 22 ° C. and 50% relative humidity.

The table below shows the composition (wt%) of acrylic block copolymer and second polymer for Comparative Example (CE) and Example (Ex), and the resulting storage modulus (G ′) at different temperatures. And tan delta (tan δ) are shown along with tensile strength and elongation at break. A blank means that the component is not added.

  Predictable variations and modifications of this invention will become apparent to those skilled in the art without departing from the scope and spirit of this invention. The present invention should not be limited to the embodiments described herein for purposes of illustration.

Claims (10)

(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer comprises:
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer A first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) A second polymer containing a polyvinyl acetal resin, which is obtained by acetalizing a polyvinyl alcohol resin with an aldehyde having 4 or more carbon atoms and an aldehyde having 3 or less carbon atoms, A polymer of
And a polymer blend substantially free of plasticizer.   The polymer blend of claim 1, wherein the polyvinyl acetal resin comprises polyvinyl butyral. (I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer comprises:
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer A first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) a polymer blend comprising a second polymer selected from at least one of polyvinyl acetate and cellulose ester.   4. The polymer blend of claim 3, wherein the cellulose ester is selected from cellulose acetate propionate and cellulose acetate butyrate.   5. A polymer blend according to any one of claims 1 to 4, wherein the first polymer comprises 20 to 60% by weight of the at least two A block polymer units.   6. A polymer blend according to any one of the preceding claims, wherein the first polymer comprises a first acrylic block copolymer and a second acrylic block copolymer.   The first acrylic block copolymer comprises 45-60% by weight of the at least two A block polymer units, and the second acrylic block copolymer comprises 20-45% by weight of the at least two A block polymer units. 7. A polymer blend according to claim 6 comprising.   An article comprising the polymer blend of any one of claims 1-7. A method for producing a polymer blend, comprising:
(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer comprises:
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer Providing a first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) a second polymer comprising a polyvinyl acetal resin obtained by acetalizing the acrylic block copolymer with an aldehyde having 4 or more carbon atoms and an aldehyde having 3 or less carbon atoms with the polyvinyl alcohol resin; Blending,
Wherein the polymer blend is substantially free of plasticizer. A method for producing a polymer blend, comprising:
(I) a first polymer comprising at least one acrylic block copolymer, wherein the at least one acrylic block copolymer comprises:
(A) at least two A block polymer units, each A block having a glass transition temperature of at least 90 ° C. and independent of the monoethylenically unsaturated monomer comprising the first (meth) acrylate monomer At least two A block polymer units derived, and (b) at least one B block polymer unit having a glass transition temperature of -30 ° C. or less and comprising a second (meth) acrylate monomer Providing a first polymer comprising at least one B block polymer unit derived from a monoethylenically unsaturated monomer;
(Ii) blending the acrylic block copolymer with a second polymer selected from at least one of polyvinyl acetate and cellulose ester.